Flow analysis in two-dimensional impeller of centrifugal pump by the surface singularity method combined with a flow-model of three-dimensional boundary layer

An iterative solution method has been developed for calculating flows in two-dimensional centrifugal pump impellers. The method was formed by combining an integral calculation method for a three-dimensional boundary layer on the whole channel wall with a surface singularity method for a two-dimensional inviscid core-flow. In the inviscid analysis, the blade shape and the area of flow passage were modified by calculated displacement thickness of boundary layer, and then a finite number of vortices were distributed on the modified blade surfaces with the Kutta condition at the outlet edge on the suction surface. This method was applied to flows in two impellers with different blade thicknesses. Comparing the results of calculated and measured flows, both were qualitatively in good agreement, including an effect of the outlet blade surface with constant radius, which showed that relative velocity near the pressure surface was faster than one near the suction surface.